The map which is based on the results of three WIN/Gallup International polls, taken in 2008, 2009 and 2015. Each asked respondents whether or not they felt religious; for each country it has included the most recent figures available.

According to the surveys, five countries tie for the title of most religious. In each of Ethiopia, Malawi, Niger, Sri Lanka and Yemen, 99 per cent of those questioned answered "yes". A further four - Burundi, Djibouti, Mauritania and Somalia - saw 98 per cent reply in the affirmative.

The most religious regions are Africa and the Middle East, with south-east Asia and Latin America not far behind. Faith is important to many southern European countries too, with 74 per cent of Italians and 71 per cent of Greek claiming to feel religious.